[Expression of microRNA-155 in inflammatory bowel disease and its clinical significance]

Objective: To explore the expression of microRNA-155 in colonic mucosa and peripheral blood in patients with inflammatory bowel disease(IBD), and to examine the clinical value and significance of microRNA-155 in the diagnosis of IBD. Methods: Quatitative reverse-transcription PCR was performed to detect the expression of microRNA-155 in 20 patients with Crohn disease(CD), 21 patients with ulcerative colitis (UC), 18 patients with IBD type unclassified(IBDU), 25 healthy people(control group), 12 patients with infection colitis and 19 patients with ischemia colitis.Receiver operating characteristic (ROC) curve was performed to analyze the clincal value of microRNA-155 in diagnosis of IBD. Results: The expression of microRNA-155 in colonic mucosa in CD, UC and IBDU group was significantly higher than that in control group(P<0.05). MicroRNA-155 expression was also significantly higher in UC group in comparison to CD group (35.4±3.0 vs 18.6±5.9, P<0.01), IBDU group in comparison to CD group (23.0±3.7 vs 18.6±5.9, P<0.05) and UC group in comparison to IBDU group (35.4±3.0 vs 23.0±3.7, P<0.01). The plasma level of microRNA-155 in UC group (55.6±2.5) and IBDU group (48.1±6.2) was significantly higher than that in control group(P<0.05), while no significant difference in CD group was observed when compared with control group(P>0.05). ROC curve shows an AUC of 0.83 and 95%CI of 0.679-0.986 of microRNA-155 expression in colonic mucosa.The sensitivity and specificity of microRNA-155 expression in colonic mucosa in diagnosis of IBD was 68.4% and 78.6%, respectively. Conclusions: MicroRNA-155 showed high expression in colonic mucosa and peripheral blood in patients with IBD.MicroRNA-155 shows promise as a biomarker in diagnosis of IBD.Furthermore, the aberrant expression indicates that microRNA-155 may be involved in pathogenesis and progression of IBD.